99FBODY

iTrader: (8)

i just swapped out my tci 3500 for a vig 4000 and now that i have swapped out stalls the car surges down to 500 and then goes back up to 900 where the idle is set. i had the car retuned but that didnt help out at all. i cant figure it out, does anyone know what this could be?

RedDemonLsX

iTrader: (2)

I have the same problem and havent been able to figure it out for awile now,it did the same thing when i had a fuddle 3600 in,and is still doing it with the PT4000..

jimmyblue

iTrader: (11)

The lighter the "flywheel" mass, the more it exposes the idle
loop's instability. I had the same problem going from stock to
a TCI3000, cleaned it up (just idle airflow settings for the
most part) and it came back again after cam swap (this time,
the mixture was jacked and made the motor "soggy". Get it
idling lean, get the airflow targets close to what you see the
motor really drawing at target idle RPM and it should come
around pretty well.

99FBODY

iTrader: (8)

its just kind of weird how when i had my tci 3500 i never had any problems with driving it and now that i have this surge problem with the vig it makes me not want to even drive it.

performabuilt

iTrader: (25)

I see this and other things to and remember any time you change anything from stock you are bound to have to compensate, A moded car that acts stock is and oxymoron. There is a trade off for everything. Some can be compensated for somewhat others cant. Its just the way it is.

99FBODY

iTrader: (8)

i know im going to have problems anytime i mod a car but i just dont understand why it was fine with a 3500 stall and now drives crappy with a 4000. i dont understand. anyone know what this could be or have the same problem?

BubaGumpShrimp

iTrader: (1)

yep got the same problem as you stated though my idle is the stock 550 rpm and when i come to a quick stop the rpms drop a bit then surge up a bit, and makes coming to a stop a jerky process and not smooth at all.. ps got a fuddle 3,800 if that matters any, never did it with my 3k midwest nor the stock convererter so who knows. As you said does suck that it happens to the point of not wanting to drive it. Im getting a new programmer (hptuners) to fix a whole mess of other problems as well as this one..

DanaliHD

iTrader: (5)

i just had my 80e rebuilt and had a SC3000 put in and it does the same damn thing only mine stalls too. holy embarrassing.

the other thing mine does is when i let off the gas at say 50mph it surges and makes a thud with each surge. I noticed while laying under the truck that if i push up on the driveshaft the trans moves and makes the same thud. WTF

BubaGumpShrimp

iTrader: (1)

your trans mount might be bad if you can move the driveshaft up and down.

deadcities

iTrader: (4)

Did you check your transmission mount? Sounds like it might be broken.

DanaliHD

iTrader: (5)

that's what the trans guy said to. I'm gonna order a poly one.

What about the surging though, especially when i let off the gas at 50mph? Odd no? Could a valve or solonoid of some sort be broken in the trans? Trans guys says it's the converter causing the issue but this is an over the phone diagnosis.

02BEAST

iTrader: (8)

Just get a wideband and go SD.

Moparnos (The SLP Guy)

iTrader: (55)

find a good tuner, you can adjust that like jimmy said

RooRnZ28

iTrader: (14)

mine also does the same thing, stutters when coming to a stop and I only have a 3000. It is really bad in reverse.... sometimes the car will want to die if i reverse too fast.

I was tuned with my stock trans, and i swapped it out for a performabuilt level 3 and their 3000 stall... so i think it is all in the tuning

performabuilt

iTrader: (25)

I think it has something to do with the weight and resistance of the converter, The PCM sees a cylinder fire and expects a certain amount of time to pass for a revolution within a certain tolerance wit the smaller lighter converters and even higher stalls which also offer less resistance this happens faster and I think th stutter etc is the PCM trying to compensate, Now I am not a tuner however i did read somewhere about crankshaft relearn? And this issue and that its somehow solved by changing parameters there or resetting not sure though.

gnictry

iTrader: (3)

it is in the tuning...mine was fixed by frost w lsxtune.com

HaulinHawk

I know its been said before,but its all in the tune and the tuners ability.I made more than a few changes to my setup and had similiar problems.My local tuner, Formato took the time to listen and fix all my issues.Find a good tuner and stick with that one.

DanaliHD

iTrader: (5)

i took it to my local trans guy. he said the play in the driveshaft i feel is normal. he too thinks the tune needs tweaking to compensate for the changes

99FBODY

iTrader: (8)

i just had it retuned because of this problem and this is the guy that has always tuned my car. so i guess its goin back there to see if he can do anything else for me.

RedDemonLsX

iTrader: (2)

Funny you say formato tuned your car because he tuned mine when my cam went in and thats when my problem started,so if that guy does have ability he didnt show it with my car.